Process for starting an internal-combustion engine and an internal-combustion engine having a starting-aid device

ABSTRACT

A process is provided for starting an internal-combustion engine, particularly a Diesel engine, having an exhaust gas turbocharger and an inlet gas supply device with at least one compressed-air reservoir which is connected with an intake pipe of the internal-combustion engine. During the starting of the internal-combustion engine, additional air is blown from the inlet gas supply device into the intake pipe until a rotational speed of the internal-combustion engine reaches a previously definable idling speed.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119 from German PatentApplication No. DE 10 2010 054 049.8, filed Dec. 10, 2010, the entiredisclosure of which is herein expressly incorporated by reference.

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates to a process for starting an internal-combustionengine. The invention further relates to an internal-combustion enginehaving a starting-aid device.

Internal-combustion engines (such as Otto and Diesel engines) are lessinclined to start at lower temperatures. In order to ensure a robuststart of the internal-combustion engine, excessively increasedquantities of fuel, among other things, are fed (“lubricating”). Majoramounts of undesirable pollutants, such as smoke particulates and HC(hydrocarbons) are therefore generated during a cold-starting operation.In most relevant emission cycles, the internal-combustion engine is tobe cold-started at least once. The emissions produced during the briefcold-starting operation correspond to a considerable fraction of whatthe internal-combustion engine emits as harmful exhaust gases during theentire emission cycle. It is therefore a challenge to developers ofinternal-combustion engines to, on the one hand, ensure thecold-starting capability of the internal-combustion engine and, on theother hand, minimize undesirable pollutants during the startingoperation. Furthermore, start-stop systems for internal-combustionengines are increasingly used for improving energy efficiency. Thesestart-stop systems require a starting of the internal-combustion enginethat is as fast as possible.

As a rule, internal-combustion engines have an electric starter motor(“starter”) that is coupled by way of a wheel gear or belt gear and hasan output just sufficient for securely starting the internal-combustionengine. Here, the dimensioning, on the one hand, is a result of the costof the starter and, on the other hand, is limited by the available powerfrom the current source (vehicle battery). This is illustrated in FIG. 1by a diagram of a course of a speed n over the time t during the startof an internal-combustion engine according to the state of the art. Afiring speed or starting speed n_(a) of the internal-combustion engineis therefore always below its idling speed_(z), which necessitates astart of the combustion operation below the stable speed limit that isdefined by the idling speed n_(z). In a starting device operation AV1,the starter will drive the internal-combustion engine until it reachesthe starting speed n_(a). Then, an ignitable fuel-air mixture will beignited at a point in time t1 (in the case of an Otto engine, by appliedignition; in the case of a Diesel engine, by self-ignition), which isindicated by a lightning symbol. For this purpose, this fuel-air mixturemay also only be injected into the combustion chamber when the startingspeed n_(a) has been reached. After that, the combustion will start. Thestarter is switched off beforehand, and the speed n of theinternal-combustion engine decreases again to a point in time t2, untilthe internal-combustion engine or the engine is accelerated by means ofthe combustion energy in an internal-combustion engine operation VM1 tothe set idling speed n_(z) and reaches a stable course at the point intime t3.

During a cold starting operation, the maximal air or mixture temperaturein the cylinder (combustion chamber) will fall because of the lowambient temperature. Particularly in the case of Diesel engines, it canhappen that the self-ignition temperature of the fuel is not reached atthe end of the compression stroke. As a result the engine possiblycannot be started at all at the starting speed n_(a). Typical measuresfor increasing the cold-starting capability are the reduction ofleakages and losses of heat, the increase of the injected or fed fuelquantity as well as diverse systems for the starting aid of thecombustion engine or of the internal-combustion engine, such as a heaterplug (“preheating”). However, this measure for improving the startingcapability will simultaneously lead to an emission problem. The reasonis that, as a result of the high quantity of fuel and the lowtemperature, the combustion takes place in an incomplete manner. Thishas the result that many particulates and hydrocarbons occur as productsof the incomplete combustion. When the air ratio (^,lambda) falls belowthe so-called soot limit (at ^≈1.2), the particulate emission will risesuperproportionally.

In addition, several systems exist for a pneumatic starting aid of aninternal-combustion engine by means of compressed air. In one case, thecompressed air can drive the turbine of a pneumatic starter motor. Inanother case, the compressed air can be introduced directly into one ormore cylinders during the power cycle in order to pneumaticallyaccelerate the crankshaft. For example, several industrial-scale Dieselengines (such as marine diesel engines or stationary systems forgenerating emergency power) have a pneumatic starting system consistingof an air compressing device, a compressed-air reservoir, a pneumaticdistributor and starter valves. The compressed air generated by an aircompressor is stored in one or more compressed-air reservoirs providedfor the pneumatic starter. The pneumatic distributor will then take overthe task of distributing the compressed air from the compressed-airreservoir to the respective starter valves in the cylinder head of theinternal-combustion engine. By way of the starter valves, the compressedair is admitted into the cylinders in order to drive the respectivepistons from the top dead center in a downward motion (while the pistonsare upright) to the bottom dead center. During the subsequent upwardmotion of the respective piston, the expanded air is discharged throughthe normal exhaust valves. The acceleration of the crankshaft takesplace purely pneumatically up to the ignition of the engine.

In the case of hybridized vehicles having an additional driving system,a starter (starter motor) is no longer necessary. An electric motor inthe hybrid drive train takes over the starting aid for the combustionengine. In addition, the higher-power electric motor is capable ofaccelerating the combustion engine directly up to its idling speed.

International Patent Document WO-2006/089779 describes a device whichtakes compressed air from the compressed-air system of a vehicle andbriefly blows it into the fresh-air supply system of a piston combustionengine with turbocharging in order to avoid the so-called “turbo-lag”.This so-called “pneumatic booster system” (PBS) forms a device for aprocess for improving the accelerating performance of the pistoninternal-combustion engine with turbocharging.

It is therefore an object of the present invention to provide animproved process for starting an internal-combustion engine.

A further object consists of creating an internal-combustion enginehaving a starting-aid device.

According to one aspect of the invention, additional air from an inletgas supply device, which is provided for a brief blowing-in of air foreliminating the so-called turbo-lag, is blown into the intake pipe whenstarting the internal-combustion engine.

Accordingly, a process for starting an internal-combustion engine,particularly a Diesel engine, having an exhaust gas turbocharger and aninlet gas supply device having at least one compressed-air reservoir,which is connected with an intake pipe of the internal-combustionengine, is provided, whereby, during the starting of theinternal-combustion engine, additional air is blown from the inlet gassupply device into the intake pipe until a speed of theinternal-combustion engine reaches a previously definable idling speed.

Such a starting aid formed by the so-called pneumatic booster systemadditionally provides the internal-combustion engine with the advantagesof improving the cold-starting capability for the inner-engine emissionreduction and also for implementing a start-stop function.

The already existing infrastructure of the PBS system can be utilizedfor efficiently and rapidly starting the internal-combustion enginewhile its emissions are low. By means of an electronic control and anintelligent communication with the engine system, various processesranging from a pneumatic starting aid to a purely pneumatic start can beimplemented by means of the PBS.

This can be provided in a first embodiment in that the following processsteps are carried out:

(S1) Driving the internal-combustion engine in a starting deviceoperation by means of an electric starter until the internal-combustionengine reaches a starting speed;

(S2) igniting the fed ignitable fuel-air mixture when the starting speedis reached; and

(S3) blowing in additional air from the inlet gas supply device andincreasing the speed of the internal-combustion engine in aninternal-combustion engine operation until a speed of theinternal-combustion engine reaches a previously definable idling speed.

After the igniting, the internal-combustion engine is acted upon by theadditional air, whereby, despite a high injection quantity of fuel, as aresult of the additional air, the air ratio reaches a clearly highervalue than in the state of the art. Hydrocarbon and particulateemissions are thereby lowered.

In a second embodiment, it is provided that the following process stepsare carried out:

(S1) Driving the internal-combustion engine by means of an electricstarter in a first starting device operation until theinternal-combustion engine reaches a previously definable intermediatespeed;

(S2) driving the internal-combustion engine by blowing in additional airfrom the inlet gas supply device and increasing the speed of theinternal-combustion engine in a second starting device operation until aspeed of the internal-combustion engine reaches a previously definableidling speed; and

(S3) igniting a fed ignitable fuel-air mixture when the previouslydefinable idling speed is reached.

No fuel is injected during the pneumatic start. The internal-combustionengine is accelerated to the idling speed; only then will the ignitiontake place. The “dirty starting phase” is completely bypassed. Noharmful exhaust gases are generated in the process.

The following process steps are carried out in a third embodiment:

(S1) Driving the internal-combustion engine in a starting deviceoperation by blowing in additional air from the inlet gas supply deviceand increasing the speed of the internal-combustion engine until a speedof the internal-combustion engine reaches a previously definable idlingspeed; and

(S2) igniting a fed ignitable fuel-air mixture when the previouslydefinable idling speed is reached.

In this case, the PBS system, which is present anyhow, is utilized as anelectronically controlled additional air system, in which case therequired infrastructure is available free of charge and canisochronously intelligently (for example, by a CAN bus linkage) in asimple manner be linked with the engine timing gear. In this case, onlya variable valve gear is still required which is also already present inmany cases. Additional components for generating and controlling thecompressed air are eliminated because they are also already present. ThePBS system is used for the pneumatic engine start and the starting aidrespectively as well as for improving the transient performance.

As a result, during the blowing-in of additional air from the inlet gassupply device, a negative valve overlap of the valves of theinternal-combustion engine can be adjusted by the variable valve gear.As a result, it is prevented that the blown-in additional air escapes toa certain extent.

In a further development, it is provided that, after the previouslydefinable idling speed has been reached, the blowing-in of additionalair from the inlet gas supply device can be adjusted after a previouslydefinable time segment. In addition, the volume of the blown-inadditional air can be adjusted by the inlet gas supply device. Thus, inthe intake phase, at the idling speed or the increased idling speed.

During the blowing-in of additional air from the inlet gas supplydevice, a flap is closed in order to prevent a return flow of theadditional air into a compressor of the exhaust gas turbocharger. As aresult, losses of pressure and volume of the additional air can befurther reduced.

It is also provided that, at predefinable points in time and/or when itsaid is required, the electric starter can be switched on. A further aidfunction is thereby provided. The starter may also be available as anemergency starter when, for example, no or no sufficient compressed airis available.

An internal-combustion engine, particularly a Diesel engine, having anexhaust gas turbocharger comprises an inlet gas supply device in anintake pipe of the internal-combustion engine; a compressed-air systemhaving at least one compressed-air reservoir that can be connected withthe inlet gas supply device; an engine timing gear and a starting-aiddevice having a control device, the starting-aid device beingconstructed for controlling the inlet gas supply device for blowing inadditional air when starting the internal-combustion engine forimplementing a process for starting an internal-combustion engine. Thisprocess may be the above-described process.

The starting-aid device comprises a control device which, as software,is a component of the engine timing gear. This results in no additionalspace requirement.

In an alternative embodiment, the starting-aid device may have aseparate control device that is connected with the engine timing gear.Advantageously, retrofitting of existing installations is therefore alsopossible.

In another embodiment, it is contemplated for the engine timing gear tobe constructed for a start-stop operation of the internal-combustionengine. The advantages of the starting-aid device and of theabove-described process can therefore be used extensively.

This can be implemented, for example, in that the engine timing gearcommunicates with a control of the inlet gas supply device, the controldevice of the starting-aid device and with a clutch/transmission controlfor implementing the start-stop operation of the internal-combustionengine by way of an electric interface. The electric interface may, forexample, be an interface of a bus system, such as a CAN bus.

The advantages and potential for cold, as well as also warm, startingprocesses resulting from the above-described process and theabove-described internal-combustion engine are the following:

(1) Improvement of the (cold) starting capability of internal-combustionengines per se.

(2) Reduction of costs of an electric starter because it can have asmaller design for extreme starting situations.

(3) Reduction of emissions during the starting operation; thereby inturn

-   -   (a) reduction of the extent of the exhaust gas aftertreatment,    -   (b) observing of tightened transient exhaust gas regulations.

(4) Reduction of the fuel consumption during the starting operation.

(5) Acceleration of the starting operation, thereby in turn

-   -   (a) making a start-stop system possible.

Other objects, advantages and novel features of the present inventionwill become apparent from the following detailed description of one ormore preferred embodiments when considered in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graphical diagram of a course of the rotational speed whenstarting an internal-combustion engine according to the state of theart;

FIG. 2 is a block diagram of an exemplary internal-combustion engineaccording to the invention having a starting-aid device;

FIG. 3 is a graphical diagram of a course of the rotational speed whenstarting the internal-combustion engine with the device of FIG. 2according to a first embodiment of a process of the invention;

FIG. 4 is a graphical diagram of a course of the rotational speed whenstarting the internal-combustion engine with the device of FIG. 2according to a second embodiment of a process of the invention; and

FIG. 5 is a graphical diagram of a course of the rotational speed whenstarting the internal-combustion engine with the device of FIG. 2according to a third embodiment of a process of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 was explained above.

FIG. 2 is a block diagram of an internal-combustion engine 1 with anembodiment of a starting-aid device 20.

The internal-combustion engine 1 is equipped with an exhaust gasturbocharger 7 and an exhaust gas recirculation system 10 and in thiscase has six cylinders 2, which can be connected by way of valves (notshown) with an intake pipe 3 and an exhaust pipe 4 (also called intakemanifold and exhaust manifold). The internal-combustion engine is, forexample, a Diesel engine of a vehicle. The intake pipe 3 is connected inseries with an inlet gas supply device 5, a charge air cooler 6, acompressor 7 a of the exhaust gas turbocharger 7, an air filter 8 and anair inlet 9. Furthermore, a compressed-air system 16 is assigned to theinternal-combustion engine 1.

The exhaust pipe 4 is connected with the exhaust gas recirculationsystem 10 and an exhaust pipe 11. The exhaust gas recirculation system10 is provided with a recirculation valve 10 a and a recirculationcooler 10 b, leads in the flow direction behind the inlet gas supplydevice 5 into the intake pipe 3 and will not be explained in detail.

The exhaust gas pipe 11 connects the exhaust pipe 4 with an exhaust gasturbine 7 b of the exhaust gas turbocharger 7 which, in the flowdirection of the exhaust gas, is connected with an emission controlsystem 12 not explained in detail, a muffler 13 and an exhaust gasoutlet 14.

The compressed-air system 16 is used, for example, for supplying apneumatic brake system of the pertaining (not shown) vehicle and, inthis case, has a compressor 17, a compressed-air regulator 18, at leastone compressed-air reservoir 19 and at least one compressed-air circuit19 a. The compressor 17 is driven by an output drive 15 of theinternal-combustion engine 1 by way of a driving device 17 b, such as aV-belt, and a drive 17 a and compresses air from the atmosphere which itfeeds to the pressure regulator 18 by way of a pressure pipe 17 c. Thecompressed-air regulator 18 is connected by way of at least one feedline 18 a with the at least one pressure vessel 19 and regulates thecompressed-air feeding for maintaining the pressure in the pressurevessel 19 in a manner not described in detail. At a compressed-aircircuit 19 a, a compressed-air feeding pipe 5 b is connected to theinlet gas supply device 5 by way of a feeding valve 5 c. The method ofoperation of the inlet gas supply device 5 is described in detail inInternational Patent Document WO-2006/089779.

Furthermore, the internal-combustion engine 1 is connected with anengine timing gear 22 by way of control lines illustrated by brokenlines. In addition to other not shown equipment, a gas pedal 23 isconnected to the engine timing gear 22. An inlet gas control line 24connects the engine timing gear 22 with the inlet gas supply device 5.An engine control line 25 establishes connections of the engine timinggear 22 with the injection devices and valves of the internal-combustionengine 1. By way of a starter control line 26, a starter 27 of theinternal-combustion engine 1 is connected with the engine timing gear22. These control lines 24 to 26 may also be components of a vehicle bussystem, for example, a CAN.

In addition, a starting-aid device 20 is provided which, in thisembodiment, has a control device 21 which is arranged in the enginetiming gear 22 and, for example, forms a component of the controlsoftware. The control device 21 can naturally also be constructed as aseparate add-on unit that is connected in a suitable manner with theengine timing gear 22.

By use of the starting-aid device 20, three different possibilities arecreated for starting the internal-combustion engine 1, which will bedescribed in the following.

For this purpose, FIG. 3 shows a diagram of a course n of the rotationalspeed when starting the internal-combustion engine 1 with thestarting-aid device 20 of FIG. 2 according to a first embodiment of aprocess according to the invention.

The internal-combustion engine 1 is driven by the electric starter 27 ina first starting device operation AV1 until it reaches the startingspeed n_(a) at the point in time t1. Then an ignition takes place byinjecting an ignitable fuel-air mixture, in which case the rotationalspeed n of the internal-combustion engine 1 in an internal-combustionengine operation VM2 together with additional air from the inlet gassupply device 5 is increased until a target speed n_(z) is reached atthe point in time t3. The additional air is blown as compressed air fromthe inlet gas supply device 5 into the intake section, i.e. into theintake pipe 3 of the internal-combustion engine 1, in that the feedingvalve 5 c is opened and the flap 5 a of the inlet gas supply device 5 isclosed. As a result, the air available for the combustion is increasedimmediately depending on the duration and volume of the blowing-in ofair starting at the point in time t1 to a definable point in time t4 forswitching off the additional air. In addition, the blown-in additionalair as compressed air pneumatically boosts the acceleration of thecrankshaft of the internal-combustion engine. A brief drop of the enginespeed n (see FIG. 1, point in time t2) will no longer occur. Thestarting phase is clearly reduced. In this case, the point in time ofthe blowing-in of the additional air is decisive. Despite the highinjection volume of the fuel, the air ratio number ^ can reach a clearlyhigher value than without this pneumatic starting aid. Since the maininfluential parameter for the hydrocarbon and particulate emission isthe air ratio number ^, a higher air excess causes a lowering of thehydrocarbon and particulate emissions.

FIG. 4 is a diagram of a course of the rotational speed n when startingthe internal-combustion engine 1 with the starting-aid device 20 of FIG.2 according to a second embodiment of a process of the invention.

The electric starter 27 drives the internal-combustion engine 1 in afirst starting device operation AV1 until it reaches a previouslydefinable intermediate speed n_(b) at the point in time t1. Neither fuelis injected, nor an ignition operation is carried out. Subsequently, theinternal-combustion engine 1 is driven purely pneumatically in a secondstarting device operation AV2 by additional air from the inlet gassupply device 5 until a target speed n_(z) is reached at the point intime t3. This means that no fuel is injected during this pneumatic startbetween points in time t1 to t3. As described above, the additional airis continuously blown in from the inlet gas supply device 5 out of thepressure reservoir/pressure reservoirs 19 into the intake pipe 3 of theinternal-combustion engine 1. This compressed air is introduced intothose cylinders whose intake valves are open. In this case, attentionshould be paid to the fact that a positive valve overlap should beavoided so that the compressed air blown in through the intake valves ofthe cylinders 2 does not immediately escape again through the exhaustvalves of these cylinders 2. A negative valve overlap can beimplemented, for example, by a variable valve gear. This can also becarried out by the valve gear 22 triggered by the starting-aid device 20by way of the engine control line 23. The additional air or compressedair from the inlet gas supply device 5 will then act upon the respectivepiston of the pertaining cylinder 2 and accelerate the crankshaft aswell as the flywheel of the internal-combustion engine 1. The blowing-inof the additional air will end only when the target speed of thestarting operation or the idling speed n_(z) of the internal-combustionengine 1 is reached, which at the earliest takes place at the point intime t3. This is followed by the ignition or the injection of theignitable fuel-air mixture in an internal-combustion engine operationVM2. The blowing-in of additional air can still be continued to adefinable point in time t4 until, for example, an air excess is nolonger necessary or the idling speed can be taken up with the lowestemissions. As a result, the “dirty starting phase” with very highemissions is completely bypassed by means of the starting-aid device 20with the help of the pneumatic aid of the inlet gas supply device 5. Inthis case, no harmful gases are generated.

FIG. 5 is a diagram of a course of the rotational speed n when startingthe internal-combustion engine 1 with the starting-aid device 20 of FIG.2 according to a third embodiment of a process of the invention.

In this embodiment, the internal-combustion engine 1 is driven purelypneumatically in a second starting device operation AV2 by additionalair from the inlet gas supply device 5 until a target speed n_(z) isreached at the point in time t1. Then the ignition or the injection ofthe ignitable fuel-air mixture takes place in an internal-combustionengine operation VM2. The blowing-in of additional air can stillcontinue to a definable point in time t4. In this case, it is alsoconceivable that the blown-in additional air can be reduced in itsvolume by means of the inlet gas supply device 5 if the feeding valve 5c is constructed, for example, as a control valve.

The process for starting the internal-combustion engine 1 with thestarting-aid device 20 utilizes the already existing pneumaticinfrastructure of the PBS system with the inlet gas supply device 5 inorder to efficiently and rapidly start the internal-combustion engine 1with low emissions. As a result of the intelligent communicationconnection of the control device 21 of the starting-aid device 20 withthe engine timing gear 22, which together from a completely electroniccontrol, the different methods of the pneumatic starting aid up to apurely pneumatic start can be implemented by means of the PBS system. Adifference consists of whether a combustion already takes place at thebeginning of the blowing-in of compressed air or when the target speedn_(x) is reached.

The invention is not limited to the above-described embodiments.

Thus, it is contemplated that the above-described starting processes ofthe internal-combustion engine 1 can be optimized by an intelligentcontrol and interaction of the PBS system with the inlet gas supplydevice 5, its flap 5 a as well as the electric starter 27. For example,the flap 5 a can be closed at the start of the activation of the inletgas supply device 5, i.e. at the beginning of the blowing-in ofadditional air, in order to prevent a return flow of the additional airinto the compressor 7 a of the exhaust gas turbocharger 7. The flap 5 acan then be opened when a certain pressure is reached in the flowdirection behind the compressor 7 a. This can be detected by way ofpressure transducers, for example, in the compressor 7 a and/or in theinlet gas supply device 5.

In the case of a start-stop system, the starting-aid device 20 can beincluded, in which case, depending on the operating condition of theinternal-combustion engine 1, the appropriate embodiment of the processaccording to the invention can be used.

The interaction with a start-stop system will be briefly described inthe following by way of an example.

The inlet gas supply device 5 has a control unit—a so-called PBScontrol—which is not shown in detail and is constructed as a separatecontrol unit or is implemented as a component part in the engine timinggear 22. This control unit of the inlet gas supply device 5 may benetworked, for example, by means of an electric interface, such as a CANbus, with other drive control devices and correspondingly communicatewith them. Other drive control devices are, among others, the controldevice 21 of the starting-aid device 20 and a clutch/transmissioncontrol.

Before the starting operation of the internal-combustion engine 1, thePBS control or the engine timing gear 22 sends a signal by way of theelectric interface to a clutch/transmission control which is part of atransmission in the drive train of a vehicle equipped with theinternal-combustion engine. The clutch control and the transmissioncontrol can be implemented in a single control device as well as in twoseparate control devices. For enabling the internal-combustion engine 1to start, the clutch control initiates that the clutch of an automatedmanual transmission, the converter lockup clutch of a convertertransmission or the two clutches of a double-clutch transmission areopened before the start of the internal-combustion engine 1. Naturally,other types of transmissions or clutches may be used. In addition, if agear is engaged, the transmission control will switch the engaged gearoff again. The clutch/transmission control device will then send anenable signal by way of the electric interface back to the PBS controlor the engine timing gear 22 for enabling the starter of theinternal-combustion engine 1 by means of the control device 21 of thestarting-aid device 20 according to the above described processes.

By way of the electric interface and the coordinated cooperation of theinternal-combustion engine 1, the inlet gas supply device 5 with the PBScontrol, the clutch and the transmission, the starting and thestart-stop function of an internal-combustion engine 1 of a vehicle canbe implemented in a simple manner by means of the inlet gas supplydevice 5 with the PBS control.

It is further contemplated that the electric starter 27 is switched onby the starting-aid device 20 in a targeted manner at the moment whenits additional “aid” makes sense.

Even if only a purely pneumatic starting takes place as in the thirdembodiment, the electric starter 27 can be used as an emergency starterif no compressed air or no sufficient compressed air is present.

LIST OF REFERENCE SYMBOLS

-   -   1 Internal-combustion engine    -   2 cylinder    -   3 intake pipe    -   4 exhaust pipe    -   5 inlet gas supply device    -   5 a flap    -   5 b compressed-air feeding pipe    -   5 c feeding valve    -   6 charge air cooler    -   7 exhaust gas turbocharger    -   7 a compressor    -   7 b exhaust gas turbine    -   7 c shaft    -   8 air filter    -   9 air inlet    -   10 exhaust gas recirculation system    -   10 a recirculation valve    -   10 b recirculation cooler    -   12 emission control system    -   13 muffler    -   14 exhaust gas outlet    -   15 output    -   16 compressed-air system    -   17 compressor    -   17 a drive    -   17 b driving device    -   17 c pressure pipe    -   18 compressed-air regulator    -   18 a feed lines    -   19 compressed-air reservoir    -   19 a compressed-air circuit    -   20 starting-aid device    -   21 control device    -   22 engine timing gear    -   23 gas pedal    -   24 inlet gas control line    -   25 engine control line    -   26 starter control line    -   27 starter    -   AV1, AV2 starting device operation    -   n rotational speed    -   n_(a) starting speed    -   n_(b) definable intermediate rotational speed    -   n_(z) target speed    -   t time    -   t1 . . . t4 points in time    -   VM1, VM2 internal-combustion engine operation

The foregoing disclosure has been set forth merely to illustrate theinvention and is not intended to be limiting. Since modifications of thedisclosed embodiments incorporating the spirit and substance of theinvention may occur to persons skilled in the art, the invention shouldbe construed to include everything within the scope of the appendedclaims and equivalents thereof.

What is claimed is:
 1. A process for starting an internal-combustionengine having an exhaust gas turbocharger and an inlet gas supply devicewith at least one compressed-air reservoir coupled with an intake pipeof the internal-combustion engine, the process comprising the acts of:during a starting of the internal-combustion engine, blowing additionalair from the inlet gas supply device into the intake pipe; and whereinthe blowing of the additional air from the inlet gas supply device intothe intake pipe during the starting of the internal-combustion engineoccurs at least until a rotational speed of the internal-combustionengine reaches a previously defined idling speed.
 2. The processaccording to claim 1, further comprising the acts of: driving theinternal-combustion engine in a starting device operation via anelectric starter until the internal-combustion engine reaches a startingspeed; igniting a fed ignitable fuel-air mixture when the starting speedis reached; and blowing in the additional air from the inlet gas supplydevice and increasing the rotational speed of the internal-combustionengine in an internal-combustion engine operation until the rotationalspeed reaches the previously defined idling speed.
 3. The processaccording to claim 1, wherein the internal-combustion engine furthercomprises a variable valve gear, the process further comprising the actsof: driving the internal-combustion engine via an electric starter in afirst starting device operation until the internal-combustion enginereaches a previously defined intermediate speed; driving theinternal-combustion engine in a second starting device operation inwhich the additional air is blown-in from the inlet gas supply deviceand the rotational speed of the internal-combustion engine is increaseduntil the rotational speed reaches the previously defined idling speed;and igniting a fed ignitable fuel-air mixture when the previouslydefined idling speed is reached.
 4. The process according to claim 3,further comprising the act of: during the blowing-in of the additionalair from the inlet gas supply device, adjusting a negative valve overlapof valves of the internal-combustion engine via the variable valve gear.5. The process according to claim 1, wherein the internal-combustionengine further comprises a variable valve gear, the process furthercomprising the acts of: driving the internal-combustion engine in astarting device operation by blowing in the additional air from theinlet gas supply device and increasing the rotational speed until therotational speed of the internal-combustion engine reaches thepreviously defined idling speed; and igniting a fed ignitable fuel-airmixture when the previously defined idling speed is reached.
 6. Theprocess according to claim 5, further comprising the act of: during theblowing-in of the additional air from the inlet gas supply device,adjusting a negative valve overlap of valves of the internal-combustionengine via the variable valve gear.
 7. The process according to claim 1,wherein after reaching the previously defined idling speed, the methodfurther comprises the act of adjusting the blowing-in of the additionalair from the inlet gas supply device after a previously defined timesegment.
 8. The process according to claim 1, further comprising the actof adjusting a volume of the blown-in additional air via the inlet gassupply device.
 9. The process according to claim 1, wherein during theblowing-in of the additional air from the inlet gas supply device, themethod further comprises the act of closing a flap in order to prevent areturn flow of the additional air into a compressor of the exhaust gasturbocharger.
 10. The process according to claim 1, wherein, atpredefinable points-in-time and/or when required, the electric starteris switched on.
 11. The process according to claim 1, wherein theinternal-combustion engine is a diesel engine.
 12. The process accordingto claim 1, wherein the blowing of the additional air from the inlet gassupply device into the intake pipe begins at a point in time that iseither before, or at a time at which the internal-combustion enginereaches its starting speed, such that the internal-combustion enginedoes not experience a drop in rotational speed during the process forstarting thereof.
 13. A process for starting an internal-combustionengine having an exhaust gas turbocharger, an inlet gas supply devicewith at least one compressed-air reservoir coupled with an intake pipeof the internal-combustion engine, and a variable valve gear, theprocess comprising the acts of: during a starting of theinternal-combustion engine, blowing additional air from the inlet gassupply device into the intake pipe; driving the internal-combustionengine via an electric starter in a first starting device operationuntil the internal-combustion engine reaches a previously definedintermediate speed; driving the internal-combustion engine in a secondstarting device operation in which the additional air is blown-in fromthe inlet gas supply device and the rotational speed of theinternal-combustion engine is increased until the rotational speedreaches the previously defined idling speed; and igniting a fedignitable fuel-air mixture when the previously defined idling speed isreached, wherein the blowing of the additional air from the inlet gassupply device into the intake pipe during the starting of theinternal-combustion engine occurs at least until a rotational speed ofthe internal-combustion engine reaches a previously defined idlingspeed.
 14. An internal-combustion engine, comprising: an exhaust gasturbocharger having an inlet gas supply device in an intake pipe of theinternal-combustion engine; a compressed air system having at least onecompressed-air reservoir connectable with the inlet gas supply device;an engine timing gear; and a starting-aid device having a controldevice; wherein the starting-aid device is operatively configured forcontrolling the inlet gas supply device for blowing-in additional airwhen starting the internal-combustion engine in order to affect astarting process of the internal-combustion engine, and the blowing-inof the additional air from the inlet gas supply device begins at a pointin time that is either before, or at a time at which theinternal-combustion engine reaches its starting speed, and continues atleast until a rotational speed of the internal combustion engine reachesa previously defined idling speed such that the internal-combustionengine does not experience a drop in rotational speed during thestarting process thereof.
 15. The internal-combustion engine accordingto claim 14, further comprising a variable valve gear.
 16. Theinternal-combustion engine according to claim 15, further comprising anelectric starter for the internal-combustion engine.
 17. Theinternal-combustion engine according to claim 14, wherein the controldevice of the starting-aid device is operatively configured as softwarethat is a component of the engine timing gear.
 18. Theinternal-combustion engine according to claim 14, wherein the controldevice of the starting-aid device is a separate component connected withthe engine timing gear.
 19. The internal-combustion engine according toclaim 14, wherein the engine timing gear is operatively configured for astart-stop operation of the internal-combustion engine.
 20. Theinternal-combustion engine according to claim 19, further comprising anelectric interface through which the engine timing gear communicateswith: a control of the inlet gas supply device, the control device ofthe starting-aid device, and a clutch/transmission control implementingthe start-stop operation of the internal-combustion engine.